The invention concerns a device for dosed dispensing of at least one flowable material component, with at least one supply container receiving the material component and having an outlet and with at least one removal means having an inlet, wherein the material component can be removed in batches from the supply container by means of a screw with controllable drive, and the supply container and the removal means can be moved relative to each other to connect the outlet of the supply container to the inlet of the removal means. The invention also concerns a supply container and a removal means for such a device and container scales comprising a removal means of the above-mentioned type.
Flowable material components, such as pasty materials, powder or granulated bulk material or the like, which are provided in supply containers, require dosed dispensing of the components to supply them to their intended use, in particular, when the dosed material components are to be supplied according to a predetermined recipe, to a mixer, a processing machine e.g. an extruder, an injection molding machine, a tablet-compressing machine, a packing machine, a conveyor or the like.
To detect the mass throughput of the discharged material components, prior art supply containers have a feed screw on their outlet side (EP 0 344 521). The feed screw is driven by a motor and disposed downstream of the outlet of the supply container which is formed e.g. as a silo, such that a desired quantity of the material component can be removed from the supply container. Dosing is effected volumetrically through the number of revolutions of the feed screw or gravimetrically, with the material component being transferred to a weighing container, and the feed screw is stopped as soon as the weighing container contains the desired amount of material. These systems are demanding and expensive due to the screw drive on each supply container, as well as inefficient, in particular for portable containers having a relatively small volume, e.g. for the allocation of chemicals, colorants, pharmaceutical substances etc.
DE 199 41 920 discloses conventional removal means comprising feed screws with a controllable drive which receive the material components to be dosed e.g. via a charging funnel. Dosing is also effected volumetrically through the number of revolutions of the screw or gravimetrically by transferring the material component into a weighing container via the screw. Disadvantageously, the material remaining in the feed screw after dosing of a material component must be disposed of and the use of such a removal means for dosed allocation of different material components produces undesired cross-contamination in the feed screw.
It is therefore the underlying purpose of the invention to propose a simple and inexpensive device which eliminates the above-mentioned disadvantages.